Hair erector muscle

The erector muscle of the hair or piloerector (also called muscle creep or arrector) is composed of smooth muscle fibers and receives innervation of the sympathetic nervous system. It is inserted into the hair follicle, in its middle section, with an oblique direction, and when the hair is tightly contracted and tipped.

The pili arrector muscles are small muscles connected to hair follicles in mammals. The contraction of these muscles causes the hair to stand up during the end [1] - familiarly known as goose bumps. Each pili arrector is composed of a bundle of smooth muscle fibers that attach to several follicles (a follicular unit), and is innervated by the sympathetic branch of the autonomic nervous system. The contraction of the muscle is therefore involuntary - accents such as cold, fear, etc. can stimulate the nervous nervous system and thus cause contraction, but the muscle is not in conscious control. The contraction of the muscles has several purposes. Its main function in most mammals is to provide insulation: air is trapped between straight hair, helping the animal to preserve it.

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